[PATCH 6/7] xhci: prevent bus_suspend if SS port resuming in phase 1

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



From: Zhuang Jin Can <jin.can.zhuang@xxxxxxxxx>

When the link is just waken, it's in Resume state, and driver sets PLS to
U0. This refers to Phase 1. Phase 2 refers to when the link has completed
the transition from Resume state to U0.

With the fix of xhci: report U3 when link is in resume state, it also
exposes an issue that usb3 roothub and controller can suspend right
after phase 1, and this causes a hard hang in controller.

To fix the issue, we need to prevent usb3 bus suspend if any port is
resuming in phase 1.

[merge separate USB2 and USB3 port resume checking to one -Mathias]
Cc: <stable@xxxxxxxxxxxxxxx>
Signed-off-by: Zhuang Jin Can <jin.can.zhuang@xxxxxxxxx>
Signed-off-by: Mathias Nyman <mathias.nyman@xxxxxxxxxxxxxxx>
---
 drivers/usb/host/xhci-hub.c  | 6 +++---
 drivers/usb/host/xhci-ring.c | 3 +++
 drivers/usb/host/xhci.h      | 1 +
 3 files changed, 7 insertions(+), 3 deletions(-)

diff --git a/drivers/usb/host/xhci-hub.c b/drivers/usb/host/xhci-hub.c
index 7df8878..fdca8ed 100644
--- a/drivers/usb/host/xhci-hub.c
+++ b/drivers/usb/host/xhci-hub.c
@@ -1123,10 +1123,10 @@ int xhci_bus_suspend(struct usb_hcd *hcd)
 	spin_lock_irqsave(&xhci->lock, flags);
 
 	if (hcd->self.root_hub->do_remote_wakeup) {
-		if (bus_state->resuming_ports) {
+		if (bus_state->resuming_ports ||	/* USB2 */
+		    bus_state->port_remote_wakeup) {	/* USB3 */
 			spin_unlock_irqrestore(&xhci->lock, flags);
-			xhci_dbg(xhci, "suspend failed because "
-						"a port is resuming\n");
+			xhci_dbg(xhci, "suspend failed because a port is resuming\n");
 			return -EBUSY;
 		}
 	}
diff --git a/drivers/usb/host/xhci-ring.c b/drivers/usb/host/xhci-ring.c
index 94416ff..6a8fc52 100644
--- a/drivers/usb/host/xhci-ring.c
+++ b/drivers/usb/host/xhci-ring.c
@@ -1546,6 +1546,9 @@ static void handle_port_status(struct xhci_hcd *xhci,
 		usb_hcd_resume_root_hub(hcd);
 	}
 
+	if (hcd->speed == HCD_USB3 && (temp & PORT_PLS_MASK) == XDEV_INACTIVE)
+		bus_state->port_remote_wakeup &= ~(1 << faked_port_index);
+
 	if ((temp & PORT_PLC) && (temp & PORT_PLS_MASK) == XDEV_RESUME) {
 		xhci_dbg(xhci, "port resume event for port %d\n", port_id);
 
diff --git a/drivers/usb/host/xhci.h b/drivers/usb/host/xhci.h
index 31e46cc..ed2ebf6 100644
--- a/drivers/usb/host/xhci.h
+++ b/drivers/usb/host/xhci.h
@@ -285,6 +285,7 @@ struct xhci_op_regs {
 #define XDEV_U0		(0x0 << 5)
 #define XDEV_U2		(0x2 << 5)
 #define XDEV_U3		(0x3 << 5)
+#define XDEV_INACTIVE	(0x6 << 5)
 #define XDEV_RESUME	(0xf << 5)
 /* true: port has power (see HCC_PPC) */
 #define PORT_POWER	(1 << 9)
-- 
1.8.3.2

--
To unsubscribe from this list: send the line "unsubscribe linux-usb" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html



[Index of Archives]     [Linux Media]     [Linux Input]     [Linux Audio Users]     [Yosemite News]     [Linux Kernel]     [Linux SCSI]     [Old Linux USB Devel Archive]

  Powered by Linux